1. Field of the Invention
The present invention relates to a transparent conductive film that has transparency in the visible light range and includes a film substrate and a transparent conductor layer provided on the substrate with an undercoat layer interposed therebetween, and also to a method for production thereof. The invention also relates to a touch panel including the transparent conductive film.
The transparent conductive film of the present invention may be used for transparent electrodes in touch panels and display systems such as liquid crystal displays and electroluminescence displays and also used for electromagnetic wave shielding or prevention of static charge of transparent products. In particular, the transparent conductive film of the present invention is preferably used for touch panels. The transparent conductive film of the invention is particularly suitable for use in capacitive coupling type touch panels.
2. Description of the Related Art
Touch panels can be classified according to the position detecting method into an optical type, an ultrasonic type, a capacitive type, a resistive film type, and so on. Resistive film type touch panels are configured to include a transparent conductive film and a transparent conductor layer-carrying glass plate that are arranged opposite to each other with a spacer interposed therebetween, in which an electric current is allowed to flow through the transparent conductive film, while the voltage at the transparent conductor-carrying glass plate is measured. On the other hand, capacitive type touch panels are basically configured to include a substrate and a transparent conductive layer provided on the substrate and characterized by having no moving part. Capacitive type touch panels have high durability and high transmittance and thus are suitable for use in vehicle applications.
For example, a transparent conductive film for the touch panels is proposed that includes a transparent film substrate, and a first undercoat layer, a second undercoat layer and a transparent conductor layer formed in this order from the film substrate side on one side of the transparent film substrate (see Patent Literature 1: Japanese Patent Application Laid-Open (JP-A) No. 2002-326301).